public class Example4_19{
  public static void main(String args[]){
    Student zhang = new Student();
    Student   geng= new Student();
    zhang.setAge(23);
   System.out.println("zhang的年龄: "+zhang.getAge());
   geng.setAge(25);
 
 System.out.println("geng的年龄: "+geng.getAge());
    }
}
